from collections import deque
n, m, k = map(int, input().split())
a = [list(map(int, input().split())) for _ in range(n)]
inf = 10 ** 9 + 1
l, r = 0, inf
while r - l > 1:
  piv = (l + r) // 2
  dist = [inf] * (n * m)
  dist[0] = a[0][0] < piv
  d = deque([[dist[0], 0]])
  while d:
    c, u = d.popleft()
    i, j = u // n, u % n
    if 0 < i:
      dis = c + (a[i-1][j] < piv)
      if dis < dist[u-m]:
        dist[u-m] = dis
        if a[i-1][j] < piv:
          d.append([dist[u-m], u-m])
        else:
          d.appendleft([dist[u-m], u-m])
    if i < n - 1:
      dis = c + (a[i+1][j] < piv)
      if dis < dist[u+m]:
        dist[u+m] = dis
        if a[i+1][j] < piv:
          d.append([dist[u+m], u+m])
        else:
          d.appendleft([dist[u+m], u+m])
    if 0 < j:
      dis = c + (a[i][j-1] < piv)
      if dis < dist[u-1]:
        dist[u-1] = dis
        if a[i][j-1] < piv:
          d.append([dist[u-1], u-1])
        else:
          d.appendleft([dist[u-1], u-1])
    if j < m - 1:
      dis = c + (a[i][j+1] < piv)
      if dis < dist[u+1]:
        dist[u+1] = dis
        if a[i][j+1] < piv:
          d.append([dist[u+1], u+1])
        else:
          d.appendleft([dist[u+1], u+1])
  if dist[n*m-1] <= k:
    l = piv
  else:
    r = piv
print(l)